Photographic products, processes, and compositions employing azo dye developers



. development of United Smtes Patent 3,183,090 PHOTOGRAPHIC PRODUCTS, PROCESSES, AND

COMPOSITIONS EMPLOYING AZO DYE DE- VELOPERS Arthur D. Jarrett, Watertown,

Corporation, Cambridge, Delaware No Drawing. Filed July 11, 1962, Ser. No. 209,230 Claims. (Cl. 96-29) This invention relates to photography and more particularly to products, compositions and processes for the photosensitive silver halide elements.

It is one object of the present invention to provide novel processes and compositions for the development of silver halide emulsions, in which novel colored developing agents are used.

Another object is to provide novel processes and compositions for the development of silver halide emulsions, in which the novel developing agent is capable of developing an exposed silver halide emulsion and imparting a reversed or positive colored image of the developed image to a superposed image-receiving material.

A further object is to provide novel products, processes and compositions suitable for use in preparing monochromatic and multichromatic photographic images.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the processes involving the several steps and the relation and order of one or more of such steps with respect to each of the others,

Mass, assignor to Polaroid Mass, a corporation of and the products and compositions possessing the features, properties and the relation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

The objects of this invention may be accomplished by the use of certain novel dyes which have the ability to develop images present in an exposed silver halide emulsion; thus they may be referred to as dye developers. These novel dyes or dye developers will be further described hereinafter.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description.

The photographic processes and compositions disclosed herein are particularly useful in the treatment of an exposed silver halide emulsion, whereby a positive dye image may be imparted to another element, herein referred to as an image-carrying or image-receiving element.

US. Patent No. 2,983,606, issued May 9, 1961, to Howard G. Rogers, discloses diffusion transfer processes wherein a photographic negative material, such as a photographic element comprising an exposed silver halide emulsion, is developed in the presence of a dye developer to impart to an image-receiving layer a reversed or positive dye image of the developed image by permeating into said emulsion a suitable liquid processing composition and bringing said emulsion into superposed relationship with an appropriate image-receiving layer. The inventive concepts herein set forth provide novel dye developers for use in such processes.

In carrying out the process of this invention, a photosensitive element containing a silver halide emulsion is exposed and wetted with a liquid processing composition, for example by immersing, coating, spraying, flowing, etc., in the dark, and the photosensitive element superposed prior to, during or after wetting, on an image-receiving element. In a preferred embodiment, the photosensitive element contains a layer of dye developer, and the liquid processing composition is applied to the photosensitive clement in a uniform layer as the photosensitive 3,183,090 Patented May 11, 1965 ace element is brought into superposed position with an image-receiving element. The liquid processing composition permeates the emulsion to provide a solution of dye developer substantially uniformly distributed therein. As the exposed silver halide emulsion is developed, the oxidation product of the dye developer is immobilized or precipitated in situ with the developed silver, thereby providing an imagewise distribution of unoxidized dye developer dissolved in the liquid processing composition. This immobilization is apparently due, at least in part, to a change in the solubility characteristics of the dye developer upon oxidation, and especially as regards its solubility in alkaline solutions. It may also be due, in part, to a tanning effect on the emulsion by the oxidized developing agent. At least part of this imagewise distribution of unoxidized dye developer istransferred, by imbibition, to a superposed image-receiving layer. The

image-receiving layer receives a depthwise diffusion,

The dye developers of this invention may be utilized in the photosensitive element, for example in, on or behind the silver halide emulsion, or they may be utilized in the image-receiving element or in the liquid processing composition. In a preferred embodiment, a coating or layer of the dye developer is placed behind the silver halide emulsion, i.e., on the side of the emulsion adapted to be located most distant from the photographed subject when the emulsion is exposed and preferably also adapted to be most distant from the image-receiving layer when in superposed relationship therewith. Placing the dye developer behind the emulsion layer, as in the preferred embodiment, has the advantage of providing increased contrast in the positive image, and also minimizes any light-filtering action by the colored dye developer. In this preferred embodiment, the layer of dye developer may be applied by using a coating solution containing about 0.5 to 8%, by weight, of the dye developer. Similar concentrations maybe used if the dye developer is utilized as a component of the liquid processing composition. In an especially useful mode of disposing the dye developers in the photosensitive elements, the dye developer is dissolved in a water-immiscible solvent and then dispersed in a gelatin coating solution.

The liquid processing composition which is used in the processes herein disclosed comprises at least an aqueous solution of an alkaline compound, for example, diethylamine, sodium hydroxide or sodium carbonate, and may contain the dye developer. In some instances, it may contain an additional silver halide developing agent. If the liquid processing composition is to be applied to the emulsion by being spread thereon, preferably in a relatively thin, uniform layer, it may also include a viscosity-increasing compound constituting film-forming material of the type which, when spread over a waterabsorbent base, will form a relatively firm and relatively stable film. A preferred film-forming material is a high molecular weight polymer such as a polymeric, watersoluble ether inert to an alkali solution, as, for example, a hydroxyethyl cellulose or sodium carboxymethyl cellulose. Other film-forming materials or thickening agents whose ability to increase viscosity is substantially unmay be adjusted HQi this invention may be repre wherein W is a carbamyl radical, Ar is anarylene group;

preferably a phenylene or naphthylene group and each Ar may be the same or different, M and X are alkylene radicals, n and p each are or 1, and each Y is an ortho or para-dihydroxyphenyl radical.

The carbarnyl radical W may be represented as a wherein R and-R each may be hydrogen or an aliphatic, e.g., alkyl or hydroxyalkyl, radical, and R and R together may be a divalent aliphatic radical, c.g., a pentamethylene radical completing, with the nitrogen atom, a piperidine ring. Preferably R and R each containsno more than 12 to carbons. The arylenegroup Ar may, if desired, be substituted by, for example, alkyl radicals.

As examples of alkylene radicals comprehended by the radicals M and X, mention may be made of radicals such -cH,-cH,-, -011,-cH-'oH,- and -oH,-cH,-(JH,- The preferred embodiment is a lower alkylene group, e.g., less than 6 carbons, and more preferably an ethylene group. It should be understood that-M and X'may be alkylene groups comprising 6 or more carbon atoms .pro-, vided that the resulting dye developer is capable of being; dissolved in the liquid processingv composition, and its oxidation product rendered immobile. 7

As examples of .dye developers within the scope of this invention, mention may. be made'of:

H 1- (4'-hydroqnlnonyleth lphenyl) -3-[N-'y(hydroxypr0pyl) -ca rbamyl] -4-(3"-hydroqu nonylmethylphenylazo) ti-pyrazoloue CII N=N rLu-onl-om-on on HO-J 7 Ila-CH1 1- (4 hyd roqulnonylethylphenyl) -3-[N- ('y-hydroxypropyl -ear bamyl] -4-(4"-hydroquinonylmethylpheuylazo)-5-pyruolone PI H HrCHfiCH 1-(4-hydr utnonylpropylphenyl)-3-(N.n-hexylcarbamyl-4- (8"- y roquluonylpropylphenylazo)-5-pytalolone CHrCHr-N=N -L g N C.H

HO- N f on Hr-CH. V

1- (4'-hydroqulnonylethylphenyl -3- N,n-hexylcarhamyl-) 4 (4''-hydroquinonylethylphenylazo) fi-pymolone (4"-hy roqutnonylpropyiphenylazo)-5-pyraz0lone 1- (4'hydro ulnonylpropylphenyl) -3- (N ,n-heptylcarbamyl 4- (3 hydroqulnonylphenylazo) -5-pyraz0lone CHg-CHg-CH JJHr-CH CH 1- (4'-hydroqulnon51pro pylphenyl) 3 glNm-hexylcarbamyll -4- (2"-methyl-5"-hy roqu nonylpropylp enylazo)-5-pyrazolone The novel dye developers of this invention may be pre pared by diazotizing and coupling a compound of the formula:

into a compound of the formula:

HoUii o-z wherein Y is the protected derivative of the orthm or para-dihydroxyphenyl group, preferably the acylated derivative thereof, Z is an alkyl radical, X, M, n, p and Ar have the same meaning as above, replacing the 3-carboxylate group with a 3-carbamyl group by reacting the product with an excess of ammonia or an amine which reactant also removes in the same step the protective groups on Y to produce the hydroxyl compounds.

Compounds within Formula B and the corresponding dihydroxyphenyl compounds are disclosed and claimed in U.S. Patent No. 3,019,254, issued January 30, 1962, to Milton Green and Helen P. Husek, and in the copending application of Elkan R. Blout, Milton Green, Howard G. Rogers, Myron S. Simon and Robert B. Woodward, Serial No. 98,287, filed March 27, 1961; the copending application of Myron S. Simon, Serial No. 196,463, filed May 21, 1962; and the copending application of Myron S. Simon, Serial No. 196,464, filed May 21, 1962.

The coupler compounds of Formula C are disclosed and claimed in the copending application of Milton Green and Phylis T. Moore, Serial No. 130,489, filed August 10, 1961.

The process of preparing 3-carbamyl-pyrazolone dyes from the corresponding 3-carboxylate-pyrazolone dye is disclosed and claimed in the copending application of 10 Milton Green, Serial No. 130,467, filed August 10, 1961 (now abandoned).

The following nonlimiting examples illustrate the preparation of dye developers within the scope of this invention:

Example 1 To a suspension of 7 g. of m-aminophenyl-hydroquinone-0,0'-diacetate hydrochloride in 200 ml. of water, was added, with stirring, 8 ml. of concentrated hydro chloric acid. The resulting suspension is rapidly cooled to 0-5" C. by a butyl cellosolve-carbon dioxide bath and a solution of 1.5 g. sodium nitrite in 30 ml. of water is added dropwise to the cooled suspension. Stirring is continued for one hour and the suspension is added dropwise, without filtering to a stirred suspension of 9.3 g. of 1 [p (2',5' diacetoxyphenylpropyl) phenyl] 3- carbethoxy-S-pyrazolone, 7 g. of sodium carbonate, 400 ml. of acetone and 300 ml. of water and ice at a temperature less than 15 C. Stirring was continued for one hour after which the product, 1 [4' propyl 4 (2",5"- diacetoxyphenyl)-phenyl]-3-carbethoxy 4 [3' (2",5"- diacetoxyphenyl)phenylazo]-5-pyrazolone, was collected by suction filtration, washed with water and dried under vacuum. 5 g. of the product was placed in a three-necked flask, fitted with a dropping funnel, a mechanical stirrer and a nitrogen inlet-outlet tube. The system was flushed out with nitrogen and 50 ml. of deaerated hexylamine was added from the dropping tube. Stirring was continued under nitrogen and the flask was treated on a steam bath for 4 hours. Excess amine was then removed by vacuum distillation and the product precipitated by the addition of dilute, deaerated hydrochloric acid. The gummy product was then washed with water and dissolved in methyl cellosolve, precipitated into dilute hydrochloric acid, filtered, and again washed with water. The product was again dissolved in methyl cellosolve, deaerated with nittrogen and added to a solution of 5 g. of sodium hydroxide in 500 ml. of water which had been deaerated with nitrogen for 30 minutes. .The product was precipitated by the addition of gaseous carbon dioxide and was filtered and washed with water. The solid was redissolved in methyl cellosolve and reprecipitated into dilute hydrochoric acid. The product, l-(4-hydroquinonlypropylphenyl) 3 (N,n hexylcarbamyl) 4 (3" hydroquinonylphenylazo)-5-pyrazolone, was collected by suc tion filtration, washed with water and dried in a vacuum. The product showed a melting point of 122-125" C. with decomposition.

' Example 2 3-(2,5'-diacetoxybenzyl)-aniline hydrochloride was diazotized and coupled into 1-(4'-[2",5"-diacetoxyphenylethyl]-phenyl)-3-carbethoxy-S-pyrazolone. The resulting compound was treated with l-amino-3-propanol in a nitrogen atmosphere. The resulting product, 1-(4-hydroquinonylethylphenyl) 3 [N ('y hydroxypropyU- carbamyl] 4 (3" hydroquinonylmethylphenylazo)- S-pyrazolone, melted at 139145 C.

Example 3 4-(2',5'-diacetoxy benzyl)-aniline hydrochloride was diazotized and coupled into 1-[4'-(2",5"-diacetoxyphenylethyl)-phenyl]-3-carbethoxy-S-pyrazolone. The resulting Example 4 m-Aminophenyl hydroquinone 0,0 diacetate hydrochloride was diazotized and coupled into 1-[4-(2,5- diacetoxyphenylpropyl) phenyl] 3 carbethoxy 5- pyrazolone. The resulting solid was treated with n-propylamine in a nitrogen atmosphere. The resulting prod- 11 net 1 (4' hydroquinonylpropylphenyl) 3 (N,npropylcar-bamyl) 4 (3" hydroquinonylphenylazo) 5- pyrazolone, melted at 133-138 C.

Example 5 3-(2',5' bisacetoxybenzyl)-aniline hydrochloride was diazotized and coupled phenylpropyl) phenyl] 3 carbethoxy 5 pyrazolone. The resulting product was treated with ethanol and ammonia in a nitrogen atmosphere. The resultingproduct, 1 (4' hydroquinonylpropylphenyl) 3-- carbamyl 4- (3"-hydroquinonylphenylazo)-5-pyrazolone, melted at l5l-155 C. V

It should ,be noted that the couplers within Formula C, compounds within Formula B and amines may be see l2 Blcndor. 5 cc. of the resulting dye dispersion was added to cc. of water containing small amounts of saponin and succinaldehyde, and then coated on the gelatin suibcoated cellulose acetate film base.

The dye developers of this invention possess a number of unobviou properties.v Thus, for example, they develop more silver than closely related dye developers disclosed in the copending application of Milton Green,

lected and combined according to the novel processes of this invention to produce a large number of dye developers within the scope .of thisinvention.

The following are examples of the photographic utilization of the dye developers of this invention and are given for purposes of illustration only. 7

Example 6 A photosensitive element was prepared by coating a gelatin subcoated film base with a solution comprising 0.089 g. g of 1-[4-hydroquinonylpropylphenyl]-3-carbamyl 4 (3' hydroquinonylphenylazo) r S-pyrazolone dissolved in 10 cc. of a solution of 2%. cellulose acetate hydrogen phthalate in acetone. After this coating dried, a blue-sensitive silver iodobromide emulsion was applied and allowed to dry. This photosensitive element was exposed, and brought into superposed relationship with an image-receiving element as an aqueous alkaline liquid processing composition comprising;

Water cc 100 NaOH g 5.17 Hydroxyethyl cellulose; (high viscosity) [commercially available from Hercules Powder Co., Wilmington '99, Delaware, under the trade name Natrosol 250] g 4.03 Sodium thiosulfate g 1.15 Benzotriazole g 0.5 N benzyl-a-picolinium bromide g 2.3

was spread between said elements. The image-receiving element comprised a 2:1 mixture, by weight, of polyvinyl alcohol and poly-4-vinylpyridine on a baryta paper support. After an imbibition' period of approximately 1 minute, the image-receiving element was separated and contained a yellow positive image.

Example 7 The procedure described in'Example 6 was repeated, except that 0.106 g. of l-(4-hydroquinonylethylphenyl)- 3 (N,n hexylca-rbamyl) 4 (3" hydroquinonylphem ylpropylazo)-5-pyrazolone was employed,- the processing composition also contained 0.2% 4-methylphenylhydroquinone, and the image-receiving element comprised a layer of the p-trimcthylammonium benzaldehyde p-tolu-- enesulfonate partial acetal of polyvinyl alcohol on baryta paper. After an imbibition period of approximately one minute, contained a yellow positive image.

Example 8 The procedures described in Examples 6 and 7 were repeated except that the dye developed was dispersed in a layer of gelatin. The coating solution fromwhich the dye developer layer was coated was prepared by adding 0.64 g. 1-(4'-hyd roquinonylpropylphenyl)-3-(N,n-hexylcar'oamyl) 4 (3 hydrsquinonyl phcnylazo) -5- pyrazolone in 0.6 cc. of N-n-butylacetanilide and 1.0 cc. of cyclohexanoneto 5 gm. of 10% gelatin solution, 1.8 cc. of water and 1.67 cc. of 5% Alkanol B. Emulsification was effected by high speed agitation in a Waring the, image-receiving element was separated and multicolor diffusion transfer processes.

-of such photosensitive elements, mention may be made of the photosensitive elements disclosed and claimed in the' Serial No. 130,468, filed August 10, 1961 (nowv abandoned in favor of application Serial No. 301,181, filed August 9, 1963, nowU. S. Patent 3,141,772, issued July group inthe 3-position requires less antifoggant than the analogous, dye developer containing a 0 H --I l-C H group.

The dye developers of this invention also exhibit less fading when exposed to-light for prolonged'periods, and less tendency to brown" or discolor, as an incident of such exposure to light, as compared withmany previous. ly known azo pyrazolone dye develops.

The dye developers of this invention have also beenv found to be unexpectedly superior to similar azo pyramlone dye developers having only a phenyl radical in the 1-position of the pyrazolone ring, examples of which are disclosed in German Patent No. 1,036,640. In addition to developing substantially more .silver particularly in the absence of an accelerating developing agent, than, for example, 1-phenyl-3-(N,n-hexylcarbamyl)4-(4'-hydroquinonylethylphenylazo)-5-pyrazolone, and also showing substantially greater light stability, the dye developers of this invention when used in diffusion transfer processes give transfer images of very lowD min., high D. max., and excellent control. quinonylpropylphenyl) 3-(N,n-hexylcarbamyl)-4- "-hydroquinonylphenylazo)-S-pyrazolone or l-(4-hydroquinonylethylphenyl) 3-N,n-hexylcarbamyl)-4-(3"-hydro-. quinonylpropylphenylazo)-5-pyrazolone are employed in.

three-color diffusion transferprocesses in place of .l-phenyl 3 (N,n-hcxylcarbamyl)-4-(4'-hydroquinonylethylphenylazo)-5-pyrazolone in a multilayer negative also,

containing a magenta dye developer and'a cyan dye developer, the resulting multicolortransfer image exhibits unexpectedly greater color separationand lower D min. 1 The dye developers of thisinvention are alsouseful in integral multilayer photosensitive elements for use in As an example copending US. application of Edwin H. Land and Howard G. Rogers, Serial No. 565,135, filed February 13,. 1956, wherein at least two selectively sensitized photosensitiv strata are superposed on a single support and are pros essed, simultaneously and without separation, with a sine common image receiving element. A suitable arrau ment of this type comprises a support carrying va. redsensitive silver halide emulsion stratum, a green-sensitive silver halide emulsion stratum and a blue-sensitive silver When, for example, l-(4'-hydrohalide emulsion stratum, said emulsions having associated therewith, respectively, a cyan dye developer, a magenta dye developer and a yellow dye developer. In one of the preferred embodiments of photosensitive elements of this type, the dye developers are disposed in separate alkalipermeable layers behind the photosensitive silver halide emulsion stratum with which they are associated.

The photosensitive elements within the scope of this invention may be used in roll film units which contain a plurality of photosensitive frames. The photosensitive elements of this invention are especially useful in composite roll film intended for use in a Polaroid Land Camera, sold by Polaroid Corporation, Cambridge 39, Massachusetts, or a similar camera structure such, for example, as the camera forming the subject matter of U.S. Patent No. 2,435,717, issued to Edwin H. Land on February 10, 1948. In general, such composite roll films comprise a photosensitive roll, a roll of image-receiving material and a plurality of pods containing an aqueous alkaline processing solution. The rolls and pods are so associated with each other that, upon processing, the photosensitive element may be superposed on the image-receiving element and the pods may be ruptured to spread the aqueous alkaline processing solution between the superposed elements. The nature and construction of the pods used in such units are well known to the art. See, for example, US. Patents Nos. 2,543,181 and 2,634,886, issued to Edwin H. Land.

It will be noted that the liquid processing composition may contain one or more auxiliary or accelerating silver halide developing agents, such as p-methylaminophenol (Metol); 2,4-diaminophenol (Amidol); benzylaminophe sol; hydroquinoae; a substituted hydroquinone such as toluhydroquinone, phenylhydroquinone, or 4-methylphenylhydroquinone; or a 3-pyrazolidone such as l-phenyl-3-pyrazolidone. These silver halide developing agents are substantially colorless, at least in their unoxidized form. It is possible that some of the dye developer oxidized in exposed areas may be oxidized by an energy transfer reaction with oxidized auxiliary developing agent.

In addition, development may be etfected'in the presence of an onium compound, particularly a quaternary ammonium compound, in accordance with the process disclosed and claimed in the copending application of Milton Green and Howard G. Rogers, Serial No. 50,851, filed August 22, 1960.

The dye developers of this invention may be used also in conventional photographic processes, such as tray or tank development of conventional photosensitive films, plates or papers to obtain black and white, monochromatic or toned prints or negatives. By way of example, a developer composition suitable for such use may comprise an aqueous solution of approximately 1-2% of the dye developer, 1% sodium hydroxide, 2% sodium sulfite and 0.05% potassium bromide. After development is completed, any unreacted dye developer is washed out of the photosensitive element, preferably with an alkaline washing medium or other medium in which the unreacted dye developer is soluble. The expression toned" is used to designate photographic images wherein the silver is retained with the precipitated dye, whereas monochromatic is intended to designate dye images free of silver.

It should be noted that the dye developers of this medium are self-sufficient to provide the desired color image and do not depend upon coupling reactions to produce the desired color. They thus provide a complete departure from conventional photographic color processes in which the color is produced by a coupling reaction between a color former" or coupler" and the oxidized developing agent, as well as so-called auto-coupling processes in which color is obtained by a reaction of the oxidized developing agent with unoxidized developing agent.

It will be apparent that, by appropriate selection of the image-receiving element from among suitable known opaque and transparent materials, it is possible to obtain either a colored positive reflection print or a colored positive transparency. Likewise, the inventive concepts herein set forth are adaptable for multicolor work by the use of special photographic materials, for example, film materials of the type containing two or more photosensitized elements associated with an appropriate number of image-receiving elements and adapted to be treated with one or more liquid processing compositions, appropriate dye developers suitable to impart the desired subtractive colors being incorporated in the photosensitized elements or in the liquid processing compositions. Examples of such photographic materials are disclosed in US. Patent No. 2,647,049 to Edwin H. Land.

As examples of useful image-receiving materials, mention may be made of nylon, e.g., N-methoxymethyl-polyhexamethylene adipamide, polyvinyl alcohol, and gelatin, particularly polyvinyl alcohol or gelatin containing a dye mordant such as poly-4-vinylpyridine. The image-receiving element also may contain a development restrainer, e.g., l-phenyl-S-mercaptotetrazole, as disclosed in the copending application of Howard G. Rogers and Harriet W. Lutes, Serial No. 50,849, filed August 22, 1960.

The dye developers herein set forth are also useful in the formation of colored images in accordance with the photographic products and processes described and claimed in US. Patent No. 2,968,554, issued to Edwin H. Land on January 17, 1961.

The novel compounds herein disclosed are also suitable for use as dyes for textile fibres, such as nylon.

In the preceding portions of the specification theexpression color has been frequently used. This expression is intended to include the use of a plurality of colors to obtain black.

Since certain changes may be made in the above products, compositions and processes without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A process of forming a photographic image in color, comprising developing an exposed silver halide emulsion in the presence of an aqueous alkaline solution comprising a dye developer of the formula:

.ir-(Mh-Y wherein Wis a O R: JLILR.

group wherein R and R are each selected from the group consisting of hydrogen and alkyl radicals and R, and R5 taken together may be a divalent aliphatic radical, each Ar is an arylene group selectedfrom the group consisting of phenylene and naphthylene groups, M and X each are alkylene radicals, n and p each is an integer from 0 to l, inclusive, each Y is selected from the group consisting of orthoand para-dihydroxyphenyl radicals, to thereby provide a predetermined imagewise distribution of unoxidized dye developer, and transferring at least a part of said imagewise dye developer by imbition to an imagereceiving layer in superposed relationship with said silver halide emulsion to impart a dye image to said image-receiving layer.

2. A process as defined in claim 1 wherein said dye developer is disposed, prior to exposure, in the photosensitive element comprising said exposed silver halide emulsion, and the solution containing said dye developer is formed by permeating said photosensitive element with an aqueous alkaline liquid capable of solubilizing said dye developer.

3. The process as defined in claim 2 whereby said liquid is introduced by being spread in a substantially uniform layer as said photosensitive element and image-receiving layer are brought into superposed relationship.

4. The process as defined, in claim 2 wherein said liquid contains a thickener for increasing viscosity and for facilitating the spreading thereof between said photosensitive element and said image-receiving layer. 7 g

' 5. A process as defined in claim 2 wherein said aqueous alkaline solution contains at least a second silver halide developing agent which is substantially colorless in its unoxidized form.

6. A process as defined in claim 1 wherein each Y is a paradihydroxyphenyl radical, each Ar is a phenylene radical, p is O, n is 1, W isa methylcarbamyl'radical and M is an ethylene radical.

7. A process as defined in claim 1 whereinsaid dyedeveloper is l-(4'-hydroquinonylpropylphenyl) 3 (N,n- 1

propylcarbamyl)-4-(3"-hydroquinonylphenylazo) 5 pyrazolone.

11. A process as defined'in claim 1 wherein said dye developer is 1-(4' hydroquinonylpropylphenyl) 3 carbamyl-4-(3"-hydroquinonylphenylazo)-5-pyrazolone.

12. A photographic product comprising a plurality oflayers including a silver halide emulsion layer, at least one of said layers containing a dye developer of the formula:

I Ar(M)uY wherein W is a o R, ll -l C-N-R;

group wherein R and-R are each selected, from the group consisting of hydrogen and alkyl radicals and R and R taken together may be a divalent radical, each Ar is an arylene group selected from the group consisting of phenylene and naphthylene groups, M and X each are alkylene radicals, n and p each is an integer from 0 to l, inclusive, and each Y is selected from the group consisting of orthoand para-dihydroxyphenyl, radicals.

13,. A product as defined in claim.l2 wherein each Y is a para-dihydroxyphenyl radical each Ar is a phenylene.

radical, pisO, n is l, W is a methylcarbamyl radical and M is an ethylene radical.

14. A process, of developing an exposed silver halide emulsion which comprises treatingsaid emulsion for a time sufficient to develop with an aqueous alkaline solution comprising a compound of the formula:

l Ar(M)uY wherein W is a o g R,

group wherein R andR are each selected from the group.

consisting of hydrogen and alkyl radicals and R and R taken together may be a divalent aliphatic radical, each Ar is an arylene group selected from the group consisting of phenylene and naphthylene groups, M and X each are alkylene radicals, n and p each is an integer from 0 to 1, inclusive, and each Y is selected from the group consisting of orthoand para-dihydroxyphenyl radicals.

15. A photographic developer composition. comprising an aqueous alkaline solution of a colorless silver halide developing agent and a dye developer ,of the formula:

group wherein R and R are each selected from the group consisting of hydrogen and alkyl radicalsand R, and R,

alkylene radicals, ,n and p each is an integer from 0 to 1, inclusive, and each Y is selected from the group consisting of orthoandpara-dihydroxyphenyl radicals.

References Cited by the Examiner UNITED STATES PATENTS 2,816,103 12/57 Schmid etal.- 260--162 2,983,606 5/61- Rogers 96-29 3,003,872 10 /61 Bloutetal. 9629 3,117,117 1/64 Berrie et a1. 260-162 6 FOREIGN PATENTS 1,036,640 8/58 Germany.

NORMAN G. TORCHIN, Primary Examiner; 

1. A PROCESS OF FORMING A PHOTOGRAPHIC IMAGE IN COLOR, COMPRISING DEVELOPING AN EXPOSED SILVER HALIDE EMULSION IN THE PRESENCE OF AN AQUEOUS ALKALINE SOLUTION COMPRISING A DYE DEVELOPER OF THE FORMULA: 